A snow squall watch for Watford, Pinery Park, and Eastern Lambton County has ended.
Environment Canada said heavy flurries developed off of Lake Huron Wednesday afternoon and intensified over the evening hours.
The national weather agency says conditions improved early Thursday morning.
A snow squall warning is posted for London-Middlesex.
Lake effect snow squalls are expected to continue Thursday morning and an additional 5 to 10 cm snow accumulations in the most persistent snow squalls are possible.